1. Field
This invention relates generally to data communications, and more specifically, to a service gateway.
2. Background
Service gateways such as firewall, server load balancers have been deployed by service providers and enterprises. In the past, service gateways were used for special purposes such as security. They are, however, used in expanded ways today. Many service providers deploy service gateways to perform various service gateway applications to examine and analyze data packets of a communication session between a host device and a server computer. Many gateway applications modify the packets to assist the analysis of the data packets and the communication sessions. Packet modification is a computation intensive and memory access intensive task. The modification task is usually performed by a processor module of a service gateway. Typically the processor or processor module analyzes a data packet, determines the necessary modification data blocks, creates a packet memory buffer, copies some data from the data packet into the data packet memory buffer and copies the modification data blocks into the packet memory buffer. When the data copying is completed, the processor has generated a new data packet from the original data packet. The service gateway then sends the generated data packet onto the network.
The data packet modification process is costly to the processor module, consuming CPU cycles and memory access bandwidth. If the data packet modification process can be offloaded and handled by a high performing hardware-based module of service gateway, the processor module can allocate its resources to handle additional data packets or additional communication sessions.
Therefore, there is a need to introduce a hardware-based high performing packet editing module to handle the data packet modification.